Formal thought disorder (FTD), or disorganized and incoherent speech, has long been considered a central symptom of schizophrenia, is an important target for cognitive rehabilitation, and is increased in people at risk for schizophrenia. The long-term objective of this application is to understand the cognitive and neural mechanisms that contribute to FTD. Previous research suggests that FTD is associated with deficits in cognitive control. However, cognitive control is a broad construct that encompasses multiple component processes. In this proposal, deficits in 2 cognitive control component processes, context processing and interference resolution, will be examined as possible mechanisms of FTD in 2 studies, 1 involving people with schizophrenia, the other involving psychosis-prone as well as healthy college students. The application will test whether: 1. Performance on a context processing task (Missing Letter), an interference resolution task (Sternberg with Interference), or both, are associated with baseline amount of FTD in an interview; and FTD is specifically associated with poor context processing rather than only with poor performance on a general working memory task (2-back); 2. Context processing and interference tasks are specifically associated with baseline amount of FTD (i.e., not due to a generalized deficit), assessed using psychometrically matched tasks; 3. Increased context processing and interference resolution demands on an experimental speech task cause an increase in FTD; in contrast, an increase in general cognitive demand (increased sustained attention) does not cause an increase in FTD; 4. Performance on context processing and interference resolution tasks (but not matched control tasks) predict increased amount of FTD on the experimental speech task. Collectively, these 2 studies have the potential to provide compelling converging evidence that context processing and interference resolution deficits contribute to FTD in people with schizophrenia and in people at-risk for psychosis.